This invention relates to premoisturized food casings containing concentrated liquid smoke coatings, and more particularly relates to such food casings wherein the smoke coatings are formed from alkali smokes.
Premoisturized food casings which contain sufficient moisture for stuffing with food product on modern stuffing equipment are known to those skilled in the art, see e.g. U.S. Pat. No. 4,867,204. Such casings are moisturized with enough water to create a plasticizing effect sufficient to make the casing flexible enough for stuffing without significant breakage. The casing is then packaged in a watertight package. The moisture content in such prepackaged casings is generally greater than about 20 weight percent but usually less than 24 weight percent. Higher percentages are possible, but are generally not used because the casing becomes so flexible as to be more difficult to handle. Further, when additives such as smoke are present, higher moistures have tended to leach such additives from the casing, to create a liquid pool containing additive substances, within the casing package. While none of these problems are critical or insurmountable, their presence is an annoyance. High moisture (greater than 24 weight percent) prepackaged food casings are thus not preferred or generally used.
Alkali liquid smoke is known for use as a smoke additive for foods. Such alkali smokes are particularly suitable for coating onto tubular food casing products for subsequent transfer to food product contained in the food casing. Such alkali smokes and their advantages and uses are for example described in U.S. Pat. Nos. 4,442,868 and 4,446,167. Briefly, smoke vapor is contacted with water to remove smoke components from the smoke vapor stream. The pH of the water is elevated to over 10 and preferably over 12 which causes otherwise insoluble tars to enter into solution. The resulting liquid smoke has much greater coloring power than non-alkali aqueous liquid smokes.
Unfortunately, there are still some problems associated with the use of alkali smokes to coat premoisturized food casings. Because of the high dissolved solids in the alkali smoke, smoke constituents sometimes build up on food stuffing equipment which interferes with processing, can cause breakage and can result in streaked product.